What was the direct cause of the of New Orleans during Hurricane Katrina in 2005

This chart lists four kinds of polymers and their sources. what can be known about all four polymers, despite their differences? they come from living things. they share ionic carbon bonds. they are at least 100 monomers long. they are made of repeating subunits.

Classify this reaction: 2al+n2-> aln.

Measurements that have similar values are: a. usually accurate b. sometimes accurate c. always accurate d. never accurate